Vinyl Polymerization of Norbornene by Bis(salicylaldiminate)copper(II)/Methylalumoxane Catalysts
作者:Carlo Carlini、Simone Giaiacopi、Fabio Marchetti、Calogero Pinzino、Anna Maria Raspolli Galletti、Glauco Sbrana
DOI:10.1021/om060173i
日期:2006.7.1
The polymerization of norbornene in the presence of different bis(salicylaldiminate)copper(II) complexes and methylalumoxane has been investigated. In all cases a high molecular weight vinyl-type polymer was obtained. The presence of electron-withdrawing nitro groups on the chelate ligand markedly increased the activity of the catalyst. The influence on the catalytic performances and polymer characteristics
Structural characterization of nitro-substituted phenoxyiminato nickel complexes; inter-molecular π–π interactions in the solid states and effect of the electron drawing groups on catalytic activity
作者:Dao Zhang、Linhong Weng、Guo-Xin Jin
DOI:10.1016/j.jorganchem.2009.11.033
日期:2010.3
Three phenoxyiminato nickel complexes [(L)Ni(PPh3)(Ph)] have been prepared by the introduction of the electron drawing nitro substitutes on ortho or para-position of phenoxy and characterized by X-ray crystallography. Experimental and theory calculation suggested that the ortho and para nitro groups may be equally responsible for the small net charge on the central metal atoms because the interplanar angles between o-nitro planes and aromatic rings (28.7-37.3 degrees) are much higher than those between p-nitro planes and aromatic rings (8.2-13.8 degrees). In the solid states of these nickel complexes there exist the short inter-molecular p-p stacking interactions with the distances of 3.5828 angstrom (ortho-nitro), 3.5844 angstrom (para-nitro), and 3.0929 angstrom (ortho- and para-nitro) between two neighboring nitro-phenyl moieties. (C) 2009 Elsevier B.V. All rights reserved.